Faculty of Technology and Metallurgy
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Item type:Publication, Electrochemical characterization of the passive films formed on niobium surfaces in H2SO4 solutions(National Library of Serbia, 2006); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Active/Passive Transition of Niobium in Strong Acid and Alkaline Solutions(Sociedade Portuguesa de Electroquímica, 2006); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Reflectivity from electrochemically protected Nb surfaces(Engineering Society of Corrosion, 2015-06-15)Corrosion resistance of fine mechanically polished and electro-polished Nb surfaces were tested by elliposmetric measurements the reflectivity at various angle of incidence. The same measurements were also repeated on electro-polished Nb surface anodic ally oxidized in 1M H2SO4 during 30 s in the potential/voltage range from 0 to 100 V. From the minimum value of measured reflectivity parallel to plane of incidence, the Brewster angle for each investigated sample was determined. The simultaneous measurements of corrosion parameters Brewster angle have shown that the values of Brewster's angle should be used for fast testing the quality of protected metal surfaces. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Optimization of Oil Extraction Process from White Mustard Seeds Using Response Surface Methodology(National and University Library of the Republic of Srpska, 2024-02-21); ; In this study, response surface methodology (RSM) was used for the determination of the effect of two process parameters (extraction temperature and extraction time) and their interaction on the yield of the total extract from white mustard seeds (Sinapis alba l.), as well as the creation of a mathematical model, 3D response surface, and the establishment of an optimal extraction region. Ethanol 96% as a green solvent was employed to separate biological compounds from white mustard (Sinapis alba l.) seeds by applying ultrasound-assisted extraction (UAE). UAE was performed at the temperature of 25, 30, and 35℃ for a duration of 30, 60, and 90 min. UAE as a modern extraction technique showed great performance, while the ethanol solvent provided a high yield of compounds. The utilized RSM design adequately fit the experimental data with a high coefficient of determination (R2= 0.9365) and low mean absolute error (MAE= 1.12242). Estimated effects for the yield of the total extract showed that the extraction time, the temperature, and the interaction between time and temperature influenced positively, while the time-squared and the temperature-squared influenced negativity on the yield of the total extract. Analysis of variance showed that 2 effects have P-values less than 0.05. The optimal yield of the total extracted oil was 15.19% at the temperature of 35℃ for a duration of 70.3 min. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Electrochemical formation of anodic oxide films on Nb surfaces: ellipsometric and Raman spectroscopical studies(SPRINGER, 2007-02); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Photoelectrochemical investigations of thermally formed films on titanium surfaces(Society of Chemists and Technologists of Macedonia, 2009-12-15)The semi-conducting and photoelectrical properties of TiO2 films prepared with thermal oxidation of titanium in the temperature range from 200 to 600 degrees C were studied. Short theoretical background for application of photocurrent in semiconductor electrochemistry was presented. For all investigated temperatures and times of thermal treatments the semi-conducting properties as photocurrent peaks and band gap energies were determined. At lower temperatures the anodic values of photocurrent peaks confirmed the existence of n-type semiconducting TiO2 films with amorphous structure. With increasing the temperature and time of thermal treatment the development of crystalline structure in the film is followed with small decreasing of band gap energy. For films formed at higher temperatures and longer time of thermal treatment the determined band gap energies are close to the 3 eV that corresponds to the rutile structure of the film. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Electrochemical behavior of tantalum in potassium hydroxide solutions(International Association of Physical Chemists (IAPC), 2018-08-31)The electrochemical behavior of tantalum in various concentrations of KOH solutions (0.1 M -10 M), was investigated using the evolution of the open circuit potentialin time, cyclic voltammetry and ellipsometricmeasurements. Depending on KOH concentrations, the open circuit potential measurements have shown three distinct behaviors concerning oxide film formation on the electrode surface and its dissolution. The cyclic voltammetry measurements were performed in various potential ranges, from -1.4 to 8 V, different concentrations of KOH solutions (0.110 M) and sweep rates ranging from 0.005 V/s to 1 V/s. In the passive region, very stable passive films were formed, which reduction has not been possible during cathodic polarization even at highly concentrated KOH solutions. In the trans-passive region, the very strong peak at 1.65 V was monitored, which nature and chemical composition is still not well known. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Active/Passive Transition of Niobium in Strong Acid and Alkaline Solutions(Portugaliae Electrochimica Acta, 2006-05-29)Mickova, Irena; Abdurauf, Prusi; Grcev, Toma; Arsov, LjubomirBy cyclic voltammetry the active/passive transition of Nb electrode has been investigated in concentration range from 0.1 M to 10 M aqueous solutions of H2SO4 and KOH. Results indicate the strong influence of the concentration and electrolyte nature to the active/passive transitions and stability of passive films. Depending on electrolyte concentrations, at potential of 1 V the calculated thickness of passive films varied from 2.2 nm to 3.2 nm. For the same concentrations of H2SO4 and KOH the formed passive films in KOH are thicker than in H2SO4. By multiple cycle sequences in which the final anodic potential is gradually enlarged, the barrier properties of passive films on Nb electrode were confirmed. In the first positive scan after the active/passive transition, no cathodic or reactivation peaks for both 1 M H2SO4 and KOH were observed. Only for higher concentrations of KOH (> 2 M) the small reactivation process was recorded. In concentration of 5 M and 10 M KOH, if after the passive film formation the Nb electrodes were maintained for 15 min at cathodic potential of -1.55 (SHE), the cyclic voltammograms indicated the complete dissolution of passive films. The voltammetric data have confirmed that the Nb electrode is more resistant in concentrated H2SO4 than in concentrated KOH solutions. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Recent Advances in Textile Functionalization Using Essential Oil-Based-Microcapsules with Antimicrobial Properties(University of Ljubljana, 2025); ; Editor-in-Chief Tatjana Rijavec; Assistant Editor Tatjana Kreže; Associate Editors Matejka Bizjak, Katja Burger Kovič, Andrej Demšar, Mateja Kos Koklič, Alenka Pavko Čuden, Andreja Rudolf, Barbara Simončič, Dunja Šajn Gorjanc, Sonja Šterman, Brigita Tomšič;Executive Editor for Databases Irena Sajovic; International Editorial Board Matej Bračič, Maribor, SI Snježana Brnada, Zagreb, HR Andrea Ehrmann, Bielefeld, DE Petra Forte Tavčer, Ljubljana, SI Jelka Geršak, Maribor, SI Marija Gorjanc, Ljubljana, SI Lubos Hes, Moka, MU Aleš Hladnik, Ljubljana, SI Svjetlana Janjić, Banja Luka, BA Mateja Kert, Ljubljana, SI Dragana Kopitar, Zagreb, HR Yordan Kostadinov Kyoshev, Dresden, DE Petra Komarkova, Liberec, CZ Mateja Kos Koklič, Ljubljana, SI Mirjana Kostić, Beograd, RS Manja Kurečič, Maribor, SI Boris Mahltig, Niederrhein, DE Subhankar Maity, Kanpur, IN Małgorzata Matusiak, Łódź , PL Ida Nuramdhani, Bandung, ID Alenka Ojstršek, Maribor, SI Roshan Paul, Aachen, DE Tanja Pušić, Zagreb, HR Ivana Salopek Čubrić, Zagreb, HR Snežana Stanković, Beograd, RS Jovan Stepanović, Leskovac, RS Dunja Šajn Gorjanc, Ljubljana, SI Mohammad Tajul Islam, Dhaka, BD Antoneta Tomljenović, Zagreb, HRAntimicrobial textiles are functionalized textiles designed to inhibit or terminate the growth of microorganisms. In light of the increasing emphasis on eco-friendly processes, the application of essential oils presents a viable alternative to synthetic drugs (antibiotics). The aim of this study was to evaluate recent advances in microencapsulation methods of essential oils with antimicrobial activity that can be applied on medical textile for dermal use by employing the PRISMA methodology. Essential oils have been microencapsulated using various methods: coacervation, spray-drying, emulsion method and in situ polymerization. Among these, coacervation is still extensively utilized, though associated scale-up challenges persist. Many essential oils have demonstrated antibacterial properties against Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) bacteria, as well as antifungal activity (Candida albicans). The growth inhibition of these microorganisms was assessed in the presence of the following essential oils and their active substances with the highest biological-antimicrobial activity: cinnamon (transcinnamaldehyde), lime (α-terpineol, terpineol, and limonene), tea tree (terpinen-4-ol), rosemary (1,8-cineole and α-pinene), peppermint (l-menthol, menthone, methyl acetate and limonene), lavender (linalool and linalyl acetate), thyme (carvacrol) and clove (eugenol). The findings indicate that functionalized textile with microcapsules exhibits enhanced antibacterial activity against Gram-positive bacteria compared to Gram-negative bacteria (Escherichia coli), which could be attributed to the bacteria’s thick wall. However, there is a notable lack of data regarding cytotoxicity and the sensory evaluation of functionalized textile. The potential utilization of essential oils was explored in the development of eco-friendlier functionalized textile with antimicrobial properties. However, additional research is required to maximize the antimicrobial activity of microcapsules to overcome challenges in the scale-up to pilot process, and to improve the immobilization in textiles. Keywords: antimicrobial properties, sustainability, essential oils, microcapsules, textile functionalization - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Electrochemical sensors based on polymer-modified screen-printed graphene electrodes for the detection of pharmaceuticals in aquatic environments(SAGE Publications, 2025-10-06);